<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .active {
            color: red;
        }
    </style>
</head>
<body>

<!--v-cloak是斗篷的意思，加载完app再显示文本-->
<div id="app">
    <h2>{{firstName}} {{lastName}}</h2>
    <h2>{{fullName}}</h2>
</div>


<script src="../js/vue.js"></script>
<script>

    const app = new Vue({
            el: '#app',
            data: {
                msg: 'hello',
                firstName: 'java',
                lastName: 'vue'
            },
            computed: {
                fullName:  {
                    set: function (newName){
                        console.log('-----',newName);
                        const names = newName.split(' ');
                        this.firstName = names[0];
                        this.lastName = names[1];
                    },
                    get: function () {
                        return this.firstName + ' ' + this.lastName
                    }
                }
            }
      })

</script>

</body>
</html>